What was pfsense's position on this, given the sg-2220 features an Atom Nxxxx ? For example what happens after 18 months if the unit bricks itself?

You should not ask here in that user forum, you should ask this at the support of netgate or pfSense directly!support@pfsense.org

I'm positive Spectrum48k did not know there was a thread previously. The 30 day ban was only meant for those not following the rules or being rude on the first thread (obviously this doesn't include you!) :)